1991 Chevrolet C1500 Silverado Standard Cab Pickup 2-door 5.7l on 2040-cars

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GM patent reveals new two-stage turbocharger

Modern turbochargers may be some of the best ever made, but performance is something that engineers are always trying to improve. According to GM Inside News, General Motors (GM) is hoping to alleviate some of the negative aspects of a two-stage turbocharger setup with a newly-patented design. The patent, that was filed on May 19, 2016, reveals a clever bypass system that allows the engine, a four-cylinder unit, to optimize both the low-pressure and high-pressure inlets for its respective functions. According to the filing, a conventional two-stage turbocharger setup is engineered to allow both turbines to operate simultaneously at low and mid engine speeds. At high engine speeds, only the low-pressure turbine works. The setup can't isolate either the low or high pressure side, which can impair low-end performance. GM's new two-stage turbocharger setup looks to eliminate this by linking the high-pressure turbo to the exhaust manifold through the high-pressure inlet duct. The low-pressure turbo is attached to the high-pressure turbo by a low-pressure inlet duct, which is linked to a connecting channel. A single actuator that is housed in the exhaust manifold creates a bypass that can opens the high-pressure inlet or close the connecting channel. Depending on what the engine load and speed is, the ECU guides the actuator—a single rotating spindle with discs corresponding to flanges on the high and low pressure sides—to isolate one of the two turbos. Isolating the turbos allow the respective inlets to be engineered for the best possible fluid dynamic performance. The setup should increase performance and decrease lag. There's no word on what car this setup will make an appearance on, but it will most likely be used in premium vehicles before trickling down to the rest of GM's vehicles. Related Video: News Source: GM Inside News, AutoGuide via GM Authority Cadillac Chevrolet GM Technology Sedan turbo patent engine turbocharging

Junkyard Gem: 1988 Chevrolet Spectrum Sport Coupe

Before General Motors created the Geo brand for cars built or designed by its overseas partners, the Chevrolet Division put its badges on U.S.-market versions of the Toyota Corolla Sprinter, the Suzuki Cultus and the Isuzu Gemini. Those cars were known as the Nova, the Sprint and the Spectrum, and all became Geos starting with the 1989 model year. Today's Junkyard Gem is one of the last Chevy Spectrums ever sold, found in a Denver self-service yard a few months ago. Midway through 1988, the Chevrolet Spectrum abruptly became the Geo Spectrum and was assigned to the 1989 model year. This car was built in May 1988, making it one of the very last of the pre-Geo Spectrums. The Chevrolet/Geo Spectrum was available as a four-door sedan and as a three-door hatchback, from the 1985 through 1989 model years. For 1988 only, a Spectrum Sport Coupe package, featuring some trim upgrades and these rad decals, could be had on the hatchback. This car was essentially identical to its Isuzu-badged counterpart, the I-Mark. In 1988, the MSRP for the cheapest possible Chevy Spectrum hatchback (the stripped-down Spectrum Express) was $6,495, while its somewhat better-equipped I-Mark twin started at $7,439 (that's $17,128 and $19,617 in 2023 dollars). Meanwhile, the base Hyundai Excel hatchback listed at $5,295 and the Yugo GV cost a hilarious $4,199 ($13,963 and $10,941 in today's money). Power came from this 1.5-liter SOHC four-cylinder, rated at 70 horsepower. A turbocharged version with 110 horsepower was available as well. You could get an automatic transmission in the Spectrum, but this car has the base five-speed manual. This car didn't get the optional air conditioning, but at least it has the traditional Isuzu HVAC control icons featuring blow-dried hair and high-heeled dominatrix boots. Just over 170,000 miles on the odometer. Someone installed a pretty good (for the 1980s) Blaupunkt Charlotte CR148 cassette deck in the dash. This was a necessity if you wanted to enjoy full appreciation of the music of the era. The Spectrum is special! It's as slick as city rain. "I didn't spend a lot of money but with my Spectrum it looks like I did." Joe Isuzu mocked Toyota salesmen when pitching the I-Mark. As was nearly always the case during the 1980s, the JDM ads for the same car were much more fun. They should have recreated this commercial with Spectrums.

NHTSA could add 1M cars to GM recall

The Detroit Free Press is reporting that the National Highway Traffic Safety Administration may expand a recall campaign for faulty brake lamps. The agency is currently looking into complaints that certain 2004-2011 Chevrolet Malibu models as well as some 2007-2009 Saturn Aura sedans may have brake lights that do not illuminate when the driver presses the pedal. Alternatively, the lamps may also illuminate without input from the driver. General Motors recalled 8,000 Pontiac G6 models from the 2005 model year for the same problem, and NHTSA is currently investigating whether to add 550,000 more G6 models built between 2005 and 2009 to the list for the same issue.
In addition, investigators are currently examining 97 complaints from Malibu and Aura owners with the same trouble. If NHTSA adds those models to the recall campaign, more than one million units could be covered. GM, meanwhile, says there have been no accidents or injuries as a result of the problem.